Automotive heating and air conditioning assembly with improved air flow and temperature control

Abstract

An improved film type air temperature control valve for an automotive HVAC assembly has a flexible, apertured belt that wraps closely around both faces of a heater core case internal to the HVAC housing. Winding and unwinding of the belt around the heater core case, and across a heater core bypass passage, simultaneously opens up more of the bypass passage as it closes off more of the heater core faces, and vice versa. Because of the close conformance of the belt to and across the heater core faces, both faces of the always hot heater core can be completely closed to direct or indirect air flow, preventing any undesired incidental heating of the air flow.

We claim: 
     
       1. An automotive heating and air conditioning assembly with improved temperature control, comprising: a hollow housing through which forced air flows;   at least one forced air outlet;   an evaporator core inside of said housing, upstream of said air outlet through which substantially all forced air flows;   a heater core located in said housing between said evaporator core and said housing air outlet, said heater core sized so as to fill less than the entire internal area of said housing, thereby leaving a bypass opening passage around said heater core, said heater core having an upstream core face oriented generally toward said evaporator core and an opposed downstream core face oriented generally toward said air outlet; and,   a flexible, retractable and extensible belt within said case housing running across said bypass passage and wrapping closely around and across both of said core faces, said belt having a plurality of windows and solid intervals sized and relatively located so as to closely cover both heater core faces and open said bypass passage in a first belt position, so as to block said bypass passage and uncover both heater core faces in a second belt position, and so as to incrementally unblock said bypass passage while simultaneously and proportionately covering said heater core faces, in inverse proportion, at belt positions intermediate said first and second belt positions,   whereby, in said first belt position, forced air flowing through said evaporator core subsequently flows only through said bypass passage before reaching said air outlet, blocked from contact with both heater core faces, and in said second belt position, forced air flowing through said evaporator flows straight through both of said heater core faces without flowing through said bypass passage, and in intermediate belt positions, forced air flowing through said evaporator flows through said bypass passage and through said heater core faces in inverse proportion.   
     
     
       2. An automotive heating and air conditioning assembly with improved temperature control, comprising: a hollow housing through which forced air flows;   at least one forced air outlet;   an evaporator core inside of said housing, upstream of said air outlet, and sized to fill substantially the entire internal area of said housing, so that forced air always passes through said evaporator core;   a heater core module located within said housing between said evaporator core and said housing air outlet, said heater core module having a heater core case sized to fill less than the entire internal area of said housing and having an upstream case opening oriented generally toward said evaporator core and a downstream case opening oriented generally toward said air outlet, said heater core module also having a blocking partition oriented across the remainder of said housing internal area not taken up by said heater core case with a bypass opening in said blocking partition;   a heater core located in said heater core case; and,   a flexible, retractable and extensible belt within said housing running across said blocking partition and wrapping closely around substantially said heater core case and closely across both of said heater core case openings, said belt having a plurality of windows and solid intervals sized and relatively located so as to closely cover both heater core case openings and open said bypass opening in a first belt position, so as to cover said bypass opening and uncover both heater core case openings in a second belt position, and so as to incrementally cover said bypass opening while simultaneously and proportionately uncovering said heater core case openings, in inverse proportion, at belt positions intermediate said first and second belt positions,   whereby, in said first belt position, forced air flowing through said evaporator subsequently flows only through said bypass opening before reaching said air outlet, blocked from flowing through either of said heater core case openings, and in said second belt position, forced air flowing through said evaporator core flows directly through both of said heater core case openings and through said heater core without flowing through said bypass opening, and in intermediate belt positions, forced air flowing through said evaporator flows through both said bypass opening and said heater core case openings in inverse proportion.   
     
     
       3. An automotive heating and air conditioning assembly with improved temperature control, comprising: a hollow housing through which forced air flows;   at least one forced air outlet;   an evaporator core inside of said housing, upstream of said air outlet, and sized to fill substantially the entire internal area of said housing, so that forced air always passes through said evaporator core;   a heater core module located within said housing between said evaporator core and said housing air outlet, said heater core module having a heater core case sized to fill less than the entire internal area of said housing and having an upstream case opening oriented generally toward said evaporator core and a downstream case opening oriented generally toward said air outlet, said heater core module also having a blocking partition oriented across the remainder of said housing internal area not taken up by said heater core case with a bypass opening in said blocking partition;   a heater core located in said heater core case; and,   a flexible, retractable and extensible belt mounted on said heater core module and extending from one reel above said bypass opening to another reel above said downstream case opening so as to run across said blocking partition and wrap closely across both of said heater core case openings, said belt having a plurality of windows and solid intervals sized and relatively located so as to closely cover both heater core case openings and open said bypass opening in a first belt position, so as to cover said bypass opening and uncover both heater core case openings in a second belt position, and so as to incrementally cover said bypass opening while simultaneously and proportionately uncovering said heater core case openings, in inverse proportion, at belt positions intermediate said first and second belt positions,   whereby, in said first belt position, forced air flowing through said evaporator subsequently flows only through said bypass opening before reaching said air outlet, blocked from flowing through either of said heater core case openings, and in said second belt position, forced air flowing through said evaporator core flows straight through both of said heater core case openings and through said heater without flowing through said bypass opening, and in intermediate belt positions, forced air flowing through said evaporator core flows through both said bypass opening and said heater core case openings in inverse proportion.